I believe you will find that most of us on this forum either use a Garrett Infinium or a Minelab Excalibur for water hunting. There are other machines out there and many of those are considered to be good machines but probably not up to speed with these two. I can tell you that before I made my decision, I did a ton of reading on both the Infinium and the Excalibur. I chose the Infinium because what I read about it appealed to me and matched my hunting style and location. I know that many other folks read as much as I did and chose the Excalibur. I would suggest that you go to Google and type in Garrett Infinium Reviews and Minelab Excalibur Reviews and see what people are saying about both. Try to identify those who are users and those who are dealers, (It is pretty obvious when you read the posts), then try to match what they say with what you expect to be your hunting style and locations.
If at all possible, the fool proof way to make the decision would be to try to rent and use both machines for more than one day if that is possible in your area. The two machines are completely different in makeup but achieve similar results in the water if you read the posts on this website from folks that use them. Both are good in fresh water and salt water.
For mid priced machines the Tesoro Sharks will do the job. The White's Beach Hunter does a good job too. The Fisher 1280 operates best in fresh water but has some problems with salt water. The Tesoro's can hold there own in fresh and salt but lack some of the advanced features of the Infinium and Excalibur. Fisher also offers the CZ 20 and 21 that get good reviews from users and is in the high end price range along with the Infinium and Excalibur for recreational users.
Absent of being able to test them all, I would consider your budget, whether you want to go new or used, how often you plan on hunting and the reading that you can absorb from other user's writings on the internet and make a choice. One comforting thing is that you can usually get your money or most of it back out of a good quality name brand machine if you take good care of it. Watch the prices on EBAY and see what machines are going for used and you will see what I mean. I bought and used a Minelab Explorer for a year back when they first came out. I bought it on Yahoo Auctions website, which no longer exists, for 700 dollars and used it for a full year. I sold it on EBAY for more than I bought it for to a fellow in Belgium. Not bad! I considered it a year long rental that I was paid to use! You may not be able to do that every time but I will bet that you can recoup most of your investment if you end up not liking your detector. That is one thing to keep in mind to give you some peace about your choice.
Good luck and don't procastinate or we will find all the gold before you do!!!!!
Can't help on the Hookah!
Jim
DaChief